Radiochemistry is a complex area of chemistry that is an increasingly important part of providing diagnostic imaging in the clinical setting. The growth in Positron Emission Tomography (PET) and Single-Photon Emission Computed Tomography (SPECT) means that researchers and clinical scientists are highly interested in synthesizing new diagnostic compounds and perfecting synthesis techniques for new radioisotopes, “tracers”, “probes” and “biomarkers”. However, because of the radioactive decay of the prepared materials, the hazard of radiation exposure to medical personnel, and the chemical instability of the radiolabeled materials, these radiation labelled compounds must generally be prepared on site and the diagnostic procedure conducted within a short period of time after the materials are prepared.
Radiochemistry has traditionally required manually intensive, bench top manipulation of chemicals with fairly standard chemical apparatus within an environment that is designed to protect the chemist from exposure of the fingers, hands, or body to radiation. Low-dose radiochemistry (<a couple of mCi) can be conducted in an appropriately reinforced fume hood with lead bricks and other types of passive shielding. High dose (curies) synthesis must be conducted in a hot cell with considerably higher shielding and safety requirements.
Manually-operated assemblies of reaction vessels, sensors, heaters, etc. are commonplace. Automated radiochemistry devices also exist (e.g., commercial FDG, methylation, etc.). However these devices are essentially optimized for a specific chemistry process and are not user configurable without having to physically manipulate hardware and reprogram the synthesis process. Existing radiochemical reaction systems are also generally not capable of performing high-pressure reactions (e.g. >50 psi).
A typical prior manual radiochemistry setup for performing radiochemistry experiments and synthesis of diagnostic materials comprises digitally-controlled hotplates and oil baths within a hot cell made of lead-bricks. Syntheses are generally followed by standard manual purification procedures.
Whether a low dose or high dose environment is involved, the increasing use of radiochemistry to perform synthesis with a variety of isotopes, including but not limited to 18F, 11C, 13N, 15O, 123I, 124I, 64Cu, 68Ga, etc. means that there is an increasing risk of radiation exposure to the chemist. Automated radiochemistry units are available, and several devices referred to as “automated synthesis modules” exist for specific types of reactions that are routinely and repeatedly conducted, including electrophilic chemistry, nucleophilic chemistry and methylation. However, these units are typically hard wired with a fixed component configuration for a specific number of reaction steps, solute volumes, and radiation levels and are notably inflexible for the experimental chemist or to handle multiple different end products. Such units typically are “black boxes” with pushbutton operation and must be physically rewired and the hardware and software reconfigured to perform a new or different synthesis step. This is in marked contrast to the visual and interactive prior art bench top manual apparatus.